After a user equipment (User Equipment, UE) gets access to a NodeB, the NodeB transmits packet service data sent by the UE to an access network through a Mobile backhaul, the access network converges the packet service data, then the access network transmits the packet service data to a Serving Gateway (Serving Gateway, SGW) through a tunnel established in a GPRS Tunneling Protocol-User plane (GPRS Tunneling Protocol-User plane GPRS, GTPU) manner, then the packet service data is transmitted to a public data network (Public Data Network, PDN) from an IP backbone (IP backbone) network and a PDN gateway (PDN Gateway, PGW), and a packet service server in the PDN serves the user equipment.
In order to satisfy personalized needs of different user groups, a Home NodeB emerges. The Home NodeB is a type of NodeB, deployed at sites such as a home, a community, a company or a school as an exclusive resource, and generally integrated on an access network. A user equipment in the Home NodeB sends packet service data to the Home NodeB, and transmits the packet service data to the PDN through a tunnel between the access network and the SGW.
For a conventional 3G core network, after the user equipment is switched into an idle state, and if downlink data arrives, a GGSN sends the downlink data to a SGSN, and the SGSN buffers the data; when the user equipment is recovered into a connection state, the SGSN delivers the buffered data to an access network. For an evolved packet core network, after the user equipment is switched into an idle state, and if downlink data arrives, the PGW sends the downlink data to the SGW, and the SGW buffers the downlink data; when the UE is recovered into a connection state, the SGW delivers the buffered data to an access network.
In the prior art, at least the following problems exist that: the access network transmits the packet service data to the SGW through the tunnel, then the SGW transmits the packet service data to the PDN through the IP backbone network and the PGW, the packet service data passes through many network entities in the transmission process, so that transmission delay of the packet service data is great, and routing is not optimized sufficiently.